Electrolytic process.



M. M/MERRITT. ELECTROLYTIC PROCESS.

APPLICATION FILED JUNE 2?, l9! 1.

1 ,2%,264L0 Patented Oct. 22, 1918.

MATTHEW M. MERRITT, 0F DANVERS, MASSACHUSETTS, ASSIGN'OR TO COPPER PROD- UCTS COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

ELECTROLYTIC PROCESS.

Specification of Letters Patent. Patented @Oii. 22, 1918- Application filed-June 27, 1917. Serial No. 177,173.

To all whom it may concern: Be it known that I, MATTHEW M. MEnRIT'r, a citizen of the United States, and a resident of Danvers, county of Essex, Commonwealth of Massachusetts, (whose post-ofiice address is Danvers, Massachusetts) have invented an Improvement in Electrolytic Processes (A), of which the following description, in connection with the accompanying drawings, 1s a specification, like characters on the drawings' representing like parts.

This invention pertains to improvements in electrolytic processes, and more particularly, though not exclusively, to improvements in depositing copper or other metal on the surface of cylindrical or other man-- drels, and of separating the deposited sheets from the mandrel to form continuous sheets, while reducing to a minimum that portion of the sheet which must be cut away to provide smooth edges therefor.

In the drawings, which show one illustrated embodiment of a preferred form of electrolyticapparatus well suited for use in connection with my novel process;

Figure 1 is a section, through an elec trolytic bath, showing in elevation a rotatable cylindrical drum which is to serve as a cathode for .the electrolytic deposit of the copper or other metallic sheet;

Fig. 2 is a diagrammatic section through a portion of the drum. i

In the drawings 1 have shown a rotatable cylindrical drum 1. partially immersed in an electrolytic bath 2, the surface of the drum serving as a cathode for the deposit of a sheet 4 of copper or other metal which is adapted to be stripped from the surface of the drum preferably in the form of a helix, so that using a drum of a glvencircumference, a sheet of copper or other metal of much greater length may be formed thereon.

1 In the preferred form of my invention, I

prefer to apply the current to, produce a slight film 6 of electrolytic deposit over the surface of the mandrel which has been previously treated with any suitable preparation 7 for preventing the permanent adhesion of the deposit to the mandrel. After a small amountof co per has been deposited upon the entire sur ace of the mandrel, I

apply on the surface of such copper deposit a non-conductive flexible element preferably forming a helix about the drum. This flexible element may take the form of the piece of string 5 coated with shellac, or a wire coated with any suitable insulating substance. I then again apply power to rotate the drum, and again apply the current to continue the electrolytic deposit until the deposited sheet is of the required thickness.

The copper may then be stripped from the mandrel, and I find that it will tear very readily along the lines of the flexible nonconductive element. It is not essential that a preliminary electrolytic deposit be made prior to the application of the flexible nonconductive element which forms the helix, but the use of the preliminary deposit is preferable because this protects the surface of the mandrel from the flexible element, and

prevents any disturbance of the preliminary coatin thereon, while, where plastics such as she lac are used on the flexible element, it prevents the deposit of such plastic on the mandrel, which would cause irregularities in metallic sheets subsequently formed thereon. In such case the deposit of such plasticv is in the metallic sheet itself, and all irregularities are confined to a very narrow strip of metallic deposit. This permits the reduction to a minimum of the edges of the sheet which need be trimmed, and under some conditions renders trimming entirely unnecessary.

The details of the bath, the construction of the drum and its operation, other than above described, form no part of the present invention, but are described and claimed in copending applications filed herewith.

'While I have illustrated one form of apparatus, and while I have described one specific embodiment of my novel process in connection with the described apparatus, it will be understood that changes in the apparatus and in the specific processes herein described may be made within the scope of the appended claims.

Claims: 1. The process of forming metallic sheets,

which comprises electrolytlcally depositing a thin sheet of metal upon a' rotating partially submerged mandrel, winding a nonconductive flexible element in a helix about said mandrel above said thin sheet, con-Z tinuing the electrolytic deposit .while rotating said mandrel until said sheet is increased in thickness to the desired extent, and removing said sheet from said mandrel by tearing along the line of the helix defined by said non-conductive flexible element.

3. The process of dividing galvanoplastic deposits formed on a rotating cathode,

which comprises electrolytically depositing a thin sheet of metal upon the surface of the cathode, locating a non-conductive element on said thin sheet along a proposed line of division, continuing the electrolytic deposit until said thin sheet has been increased in thickness to the desired extent, and then tearing said sheet along a line defined by said non-conductive element.

p In testimony whereof I have signed my name to this specification.

MATTHEW M. MERRITT. 

